Art Garfunkel has said a major factor in the break-up of Simon & Garfunkel was the 1970 movie version of Catch-22. In the late 60s, the 71-year-old recalled, both he and Paul Simon were cast in Mike Nichols' adaptation of Joseph Heller's novel. But whereas Garfunkel received fourth billing, Simon's minor role never made the final cut.

Garfunkel was speaking at a recent event in New York, after a screening of Charles Grodin's 1969 documentary about the duo, Songs of America, where both he and Grodin pointed the finger at Nichols.

"You don't take Simon & Garfunkel and ask them to be in a movie and then drop one of their roles on them. You just don't do that," Grodin said.

Garfunkel agreed. "Yes, Chuck's gone right to the heart of the difficulty in Simon & Garfunkel when he says, 'Artie and Paul were cast for Catch-22, and Paul's part was dropped,'" he said. "I had Paul sort of waiting: 'All right, I can take this for three months. I'll write the songs, but what's the fourth month? And why is Artie in Rome a fifth month?' What's Mike doing to Simon & Garfunkel?'"

These events have never been a secret: The Only Living Boy in New York, one of Simon & Garfunkel's final songs, was written as Simon waited for Garfunkel to return from shooting. But according to Garfunkel, these tensions led directly to the duo's split in 1970.

Simon & Garfunkel parted after the release of Bridge Over Troubled Water, though they have frequently reunited since. Their last concerts, in 2010, were cancelled owing to Garfunkel's vocal cord paresis. "It's getting mostly better; I'm pretty much there," he said last week. "I'm starting to book small shows – warm-up things, workout places. So I'm back to 14-years-old, with the vulnerability of an audience and the nervous energy of, 'Will the voice be there?'"